Add the following code in your site, inside the head tag:

<script>
    function SocialShare(url) {
        window.open('https://veloslidex.com/share?url=' + url, '', 'height=600,width=800');
    }
</script>

Then place the share button after changing the URL you want to share to your page HTML:

<button onclick="SocialShare('http://yoursite.com/')">Share</button>

Example: Compartilhar